Saturday, 2 May 2020

nanoVNA-F

VECTOR NETWORK ANALYSER



Having recently borrowed a friend's antenna analyser, I was interested in buying one for my shack, but the cost of the MFJ's was approaching £400 which seemed a bit excessive considering the amount of use such a device would have, so I looked for something else.

I knew about the nanoVNA because some friends had bought them and they looked great, but the screen seemed a little small, but then I noticed that there was a new "F" model which had a 4.3" screen and it came with a steel case!


Here's a video of the device just as it arrived through the letterbox..


CLICK TO PLAY VIDEO

I was very impressed with the package initially but then realised that the outer case didn't offer that much protection after all - well it certainly wouldn't withstand much pressure and the screen was very close to the flexible plastic case.

Luckily, I had a foam-filled Pelican Case which came with my used LDG-817, so I thought I'd see if it fit inside. It did!!


 

The screen would normally be placed face-down

Thankfully, I could retain the use of the protective foam which came with the nanoVNA and it left me with space to store additional adapters and cables.

With that little job sorted, I ran the Calibration procedure and saved it. I then connected my EFHV to see how it looked across the bands. Here are the results.....










The nanoVNA-F shows that the EFHW from www.wirelessantennas.co.uk is a great bit of kit. It does superbly on Top-Band, something which I've never been able to use before. At the other end of the scale (6M SSB) it fairs less well at an SWR of 2.35 but still well within the reach of my radio's ATU.

Operating the VNA-F is pretty straightforward even for a luddite like myself. Once you're in SWR Mode, you simply enter a Stop and Start frequency range such as 144MHz to 146MHz and it's done!

Rather than do a sweep across a few bands, I preferred to sweep individual bands. A little more work entering the freq-range each time, but a nice way to see any peaks and troughs in detail.

This is day one and so I'll have more play-time with it later. For one, it needs the FirmWare updating but that needs care taking due to the number of people who are making these VNA's and the minor differences between them - you could end up updating with a bin-file meant for a slightly different version.


So how does this compare with the MFJ?? Well I must admit, I do like the clunkiness of the old 259/269 and I like the simplicity of twiddling knobs and reading a simple LCD display.

But the nanoVNA-F is much cheaper and it still comes with a very nice steel case. You can do allsorts of exrta stuff with a VNA and of course it's upgradable with new firmware. 

And then there's all the stuff you can do with the computer software that's available out there!

So yes, it's a big thumbs up from me so far. Let's just hope I don't turn it into a paperweight when I do the FW update :-) 





73, Tom, M7MCQ




UPDATE : 3 |May|2020

I did the update, it was a piece of cake. Now works up to 1.5GHz and has some other features and changes. I also put some small rubber feet on each side of the vna to prevent the surfaces being scratched when laid down.

FirmWare Update 0.1.4


I also ran calibrations on five frequency ranges which are saved to memory....

Mem-0   1~30MHz
Mem-1   45~75MHz
Mem-2   118~148MHz
Mem-3   420~450MHz
Mem-4   450~1.5GHz

In addition to the usual OPEN, SHORT, LOAD and THRU, I did the ISOLN by connecting two 50 Ohm loads. Not sure if it's completely necessary, but hey-ho.

Thanks for visiting - please take a minute to leave a comment below 

73, Tom, M7MCQ.

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